http://www.brightstorm.com/math/trigonometry/basic-trigonometry/trigonometric-ratios-cosine
This website has three different videos, each about different parts of the cosine ratio. The first is a brief explanation of the definition and how to identify it. The other two videos are practice problems worked out and explained.

Emily W



http://www.teacherschoice.com.au/maths_library/trigonometry/cosine_ratio_1.htm
The above link is helpful for those who do not remember what the cosine ratio formula is, how to identify it, or who want to see it all worked out in front of them.
Cassie O



http://www.classzone.com/cz/books/geometry_2007_na/resources/htmls/athometutor/media/ii.html?chapter=7&lesson=6&state=MO
This is our book website. The link above reteaches the lesson for cosine and sine ratios. Also on the website's @home tutor are links to extra help and games.

Meaghan C